This invention relates to the precipitation of solutes from solution generally, and particularly to the desalinization of sea water.
Various methods have been used to desalinate sea water. One such method which uses reverse osmosis membranes and gels with ion-selective matrices is described, for example, in U.S. Pat. No. 4,147,622, entitled "Process for Manufacturing Membranes for Osmotic Separation", issued Apr. 3, 1979 to D. G. Nussbaumer. One problem with this osmotic separation method is that, with the passage of time, the filters become clogged and must be maintained (cleaned or changed) frequently.
Another method which uses a distillation process is described, for example, in U.S. Pat. No. 4,891,140, entitled "Desalinization Process", issued Jan. 2, 1990 to J. A. Burke, Jr. A disadvantage in using this distillation process is that it is too energy intensive.
Still another method, which uses a freezing process, is described for example in U.S. Pat. No. 4,164,854, entitled "Desalinization Method with Mercury Refrigerant", issued Aug. 21, 1979 to J. K. Martin. A disadvantage with employing this method is that, generally, it requires the acquisition and use of bulky refrigeration equipment.
A system or method which avoids these disadvantages and problems, therefore, is clearly needed, and would be very useful.